I think it would be nice to have an option to keep comments hidden by default, like they used to be on Stack Overflow some time ago. It could be on by default, but honestly, I'm not interested in most comments I end up reading and they just clutter the screen.

Please introduce such a preference - browsing the answers is currently a pain at times. If you are not interested in an answer you are not interested in the comments to that answer. So if there are many uninteresting answers or many answers you have already seen, it is now quite hard to find the interesting ones.

I propose two more ideas to do this:

The preference should not be whether comments are shown or hidden, but the number of comments shown. So you can show 0, 5 or 20 per answer, as you like.

There could be buttons "show all comments" (or perhaps show top 5 comments) / "hide all comments" for the question as well. These buttons should apply to all answers to the question at the same time. So you can have easy searchability even though your preference is to hide the comments. (Just click "show all answers" and search.)

Atwood: That's right. Well one thing we just rolled out was, we're surfacing some of the comments on the question page now, one thing I didn't like about comments was that they were essentially unsearchable, because they were loaded through Javascript, and through Ajax

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Pryor: But technically you can go back to the old way if you want, you said. Are you going to allow that in the settings?

Atwood: Yeah, we're not big on preferences, I'm kinda down on preferences as a design technique?

Spolsky: You mean the user chooses their preferences?

Atwood: Yeah! I think that your default should be good enough for like, more than 95% of the people? Otherwise you're kind of screwing up.

Spolsky: Well anyway yeah..

Atwood: But in this case I actually believe that this is a preference that we will add to the system because you could make the argument that you really don't want to see comments unless they're really really good or maybe not even at all. So you can actually set the threshold at which they get escalated to the question page? Right now the threshold is 0 essentially, the last 5 comments will appear if there are 5 comments, and then..

[...]

Atwood: But I felt with comments that it made more sense to escalate them to the page, you have to do it in a way that you're not overwhelming the page with comments, so it's top 5, by date or by voting – if we have enough votes then we'll show you the top 5 by votes.

Pryor: So the threshold is set to 5 by default?

Atwood: The total number threshold is set to 5, we're thinking about adding a threshold variable in that, the comments that are escalated to the main page have to have n votes to even appear at all – in a user preference. Like you could set it to 5 and then the only comments that got voted to 5 or higher would actually be escalated to the main page for you.

Spolsky: What would be the name of that user preference? Like what would the little radio button say?

Atwood: I don't know! I don't know that one...

Spolsky: It seems a little too complicated I mean, unless you experience that, you may not know how to set that preference.

Atwood: Yeah, well it's an advanced user setting, but some users really objected to comments being on the page at all?

Spolsky: They just, you know what? You mean you got feedback, somebody sent you an email saying they don't like comments...

Atwood: Yeah! There's not a lot, there's a minority but..

Spolsky: Yeah. Forget it. You could do anything. You could change it so that there's a button you click and it sent you money in the mail, $20 bills

Spolsky: When you click that button $20 bills arrive in the mail? And you would get somebody saying "Why did you change stack overflow? It was PERFECT"